//
// Created by ErikLu on 2020/3/14.
//

#include <iostream>

using std::cout;
using std::endl;

int main(){
    unsigned u =10,u2=42;
    std::cout<<u2-u<<std::endl;
    std::cout<<u-u2<<std::endl;

    int i=10,i2=42;
    std::cout<<i2-i<<std::endl;
    std::cout<<i-i2<<std::endl;
    std::cout<<i-u<<std::endl;
    std::cout<<u-i<<std::endl;

    return 0;
}